Periostat (Doxycycline)

(℞) Prescription Required

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Periostat 20mg

Product of United Kingdom
Manufactured by: Alliance Pharmaceuticals
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Periostat 20mg
Product of United Kingdom
Manufactured by Alliance Pharmaceuticals
Top Brand Choice
Top Generic Choice

Periostat 20mg

Product of Canada
Manufactured by: Pendopharm
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Periostat 20mg
Product of Canada
Manufactured by Pendopharm
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Periostat (Doxycyline) Dosage and Side Effects

Doctors prescribe PERIOSTAT to prevent malaria and treat a wide range of infections, including:

  • Pneumonia and other respiratory tract infections
  • Lyme disease
  • Skin infections
  • Infections involving the genitals and urinary tract infections (UTI)
  • Anthrax (after inhalational exposure)

PERIOSTAT is often used to treat bacterial infections in dogs, cats, and other animals.

Warnings and Precautions

You should take this medication only to treat bacterial infections, and it's important to take it exactly as your doctor prescribes.

Using PERIOSTAT or other antibiotics incorrectly or using them to treat infections caused by other types of germs, such as viruses, contributes to the development of drug-resistant bacteria.

Every time you take an antibiotic, it kills the sensitive bacteria. Resistant germs, however, can grow and multiply, and then surviving bacteria can become resistant.

It's also important to understand that taking antibiotics, including PERIOSTAT, alters the normal balance of bacteria in your body.

In addition to killing harmful bacteria, the medication can also reduce the amount of good bacteria that help keep other germs in check.

As a result, some people taking PERIOSTAT develop yeast infections and antibiotic-related diarrhea.

Taking PERIOSTAT could make oral birth control pills less effective. If you are on oral contraceptives, you should use other forms of birth control while you take this antibiotic.

Before taking PERIOSTAT, let your doctor know if you're going to have any kind of surgery, including dental surgery.

Your doctor also needs to know if you've ever had liver or kidney disease.

Also tell your doctor if you have diabetes. Taking PERIOSTAT can interfere with tests for sugar in the urine.

Talk with your doctor before changing your diet or your diabetes treatment plan.

Pregnancy and PERIOSTAT

Pregnant women should not take PERIOSTAT because the drug can be harmful to an unborn baby.

Tetracyclines, including PERIOSTAT, also pass into breast milk, so women who are breastfeeding should not take this drug.

If you're a woman, let your doctor know if you are pregnant, plan to become pregnant, or are breastfeeding.

It's also important to note that unborn babies exposed to PERIOSTAT or children younger than 8 years old who take the drug may have permanently stained teeth.

Children younger than 8 should not take PERIOSTAT except as treatment for inhalational anthrax or if a doctor decides it's necessary.

PERIOSTAT for Dogs and Cats

PERIOSTAT is often used to treat bacterial infections in dogs, cats, and other animals.

PERIOSTAT may be prescribed to treat several bacterial infections, such as leptospirosis, urinary tract infections (UTI), toxoplasmosis, erlichiosis, or mycoplasma.

It's also used to treat tick-borne diseases, including Lyme disease and Rocky Mountain spotted fever.

Because PERIOSTAT can cause severe side effects in dogs and cats (such as nausea and diarrhea), it should be used only under the care and direction of a veterinarian.

Side Effects

Common Side Effects of PERIOSTAT

Common side effects of PERIOSTAT include:

  • Diarrhea
  • Itching of the rectum or vagina
  • Sore mouth

Serious Side Effects of PERIOSTAT

Serious side effects of PERIOSTAT can also occur.

If you have any of these side effects, stop taking PERIOSTAT and call your doctor right away:

  • Severe headache
  • Blurry vision
  • Rash or hives
  • Trouble breathing or swallowing
  • Sunburn
  • Yellowing of the skin or eyes
  • Dark-colored urine
  • Light-colored bowel movements
  • Loss of appetite
  • Nausea or vomiting
  • Stomach pain
  • Extreme tiredness or weakness
  • Confusion
  • Less frequent urination

Interactions with this medication

PERIOSTAT Drug Interactions

Certain drugs may affect the way PERIOSTAT works. This antibiotic could also interact with other medications.

It's very important to let your doctor know about everything you're taking, including street drugs as well as any over-the-counter (OTC) medications, herbs, or supplements.

Types of drugs that interact with PERIOSTAT include:

  • Antacids
  • Calcium supplements
  • Iron supplements and laxatives that contain magnesium
  • Penicillin
  • Blood thinners, such as warfarin (Coumadin)
  • Barbiturates and anti-seizure drugs, such as carbamazepine (Tegretol) and phenytoin (Dilantin)
  • Oral birth control pills

Other PERIOSTAT Interactions

PERIOSTAT could upset your stomach.

Taking the drug with milk or food might help, but that may reduce the amount of medication your body can absorb from your stomach.

If you experience an upset stomach while taking PERIOSTAT, talk with your doctor about the best way to take this drug.

Taking PERIOSTAT could also make your skin more sensitive to sunlight. While you are on the medication, be sure to avoid sun exposure whenever possible.

If you do need to be outside, take precautions to protect your skin from the sun, such as:

  • Wearing protective clothing,
  • Wearing sunglasses
  • Applying sunscreen

If you're taking PERIOSTAT to prevent malaria, it's important to understand that the drug does not fully protect you from this infection.

While you are on the drug, you must still take additional preventative measures, including:

  • Applying effective insect repellent
  • Using mosquito nets
  • Wearing clothing that covers your whole body

PERIOSTAT and Alcohol

It's possible to drink alcohol while taking PERIOSTAT, but use of alcohol may increase your risk of side effects, including stomach upset.

Talk with your doctor about the risks of combining alcohol and PERIOSTAT.

Proper Use of this medication

For the prevention of malaria, you should start taking PERIOSTAT up to two days before traveling.

Continue taking the drug for four weeks after you leave an area where malaria is a risk.

Do not take PERIOSTAT to prevent malaria for more than four months.

The correct dosage for children older than 8 will depend on the child's weight.

Continue to take PERIOSTAT until your course of treatment is finished, even if you feel good.

Don't stop taking the medication unless directed by your doctor.


Don't take more PERIOSTAT than your doctor prescribed.

Taking too much of the medication can increase your risk for developing side effects.

If you or someone else has symptoms of an overdose, call a poison control center.

If someone collapses or isn't breathing, call 911.

Missed Dose of PERIOSTAT

Be sure to take PERIOSTAT exactly as your doctor prescribed.

Skipping doses or not completing the full course of therapy could make the drug less effective.

It could also lead to the development of drug-resistant bacteria ("superbugs") that will not respond to antibiotics in the future.

If you forget to take a dose of PERIOSTAT, take the missed dose as soon as you remember it.

If it's almost time for your next regular dose, however, skip the missed one.

Don't take twice as much PERIOSTAT at one time to make up for a missed dose.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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